freebo86 291 Posted February 24, 2021 Here we go. Struggling to get cylinder head off, 2 Share this post Link to post Share on other sites
freebo86 291 Posted February 24, 2021 (edited) Well cylinder head is off. Parts are on table. I took a inspection of some of these components and from my limited knowledge they look fine to me. But I’ll let the experts chime in. What’s of concern looking to me is the exhaust valve. But again, who am I to judge. - Few things I checked. - Wrist pin within spec - cylinder head is not warped - Push rods are true and straight - the rocker cups? Are good inside that the push rods push against. - cylinder looks good too, no scorching. - Piston has carbon build up - Took the top ring off the piston, pushed it into the cylinder head square measured gap between and it seemed to be within service limit too. - Some build up around the piston at the top looked like old oil? Some photos. What’s everyone’s thoughts? If you need better photos let me know. Didn’t pull the front crankcase cover tonight that’s tomorrow’s task. Edited February 24, 2021 by freebo86 Share this post Link to post Share on other sites
_Wilson_™ 6,563 Posted February 24, 2021 i see scoring, need better pics of the cylinder bore, take that black and white towel out and take some more pics, but from what i can see yep scoring, and oil burning plus looks to be a valve seal leeking. Share this post Link to post Share on other sites
retro 4,048 Posted February 24, 2021 Pics are a bit to blurry... camera was too close I think. Can ya take some more? I'd like to see just the top of the bore on the right side (thrust side) of the cylinder. Two piston pics... one each taken of the piston sides showing each of the skirts & ring lands. A pic showing both valve stem tips (wipe oil off them). The wrist pin looks a bit galled where the top of the rod rides. Can you see any galling inside the top of the rod bore? Take the wrist pin and push the best looking end of it into the top of the rod until the wrist pin barely pokes out of the opposite side of the rod. Then using the wrist pin for leverage, wiggle the pin straight up and down in the top of the rod. Is there any play there? Is the top (or bottom) edge of the top piston ring super sharp, like sharp enough to cut ya? What do the top ring gap measure when pushed down squarely to about 1/4 the stroke distance from TDC? Does it measure the same 1/2 way down and 3/4 the way down the bore from TDC? Can you see remnants of the original crosshatch hone pattern inside the bore, or is the bore worn smooth & shiny? Any scoring on the thrust side of the bore? Share this post Link to post Share on other sites
Wheeler 2,525 Posted February 24, 2021 My hunch earlier was correct.. oil blow by. 1 Share this post Link to post Share on other sites
_Wilson_™ 6,563 Posted February 24, 2021 yue ^^^ some how i missed post one, on page 9 (bcs alerted me to it) so i think now it's becoming very clear ... what's been going on, my next question would be if this bike was sunk by the PO, or the oil changes were not done like they should have been,, or was is run without an air filter, IMO something had to have caused this engine wear other then normal operation. 1 Share this post Link to post Share on other sites
Wheeler 2,525 Posted February 24, 2021 Yup second pic of cylinder is scored for sure.. plain as day! Rag in back ground or not. I say F-IT @freebo86.. u want a fun bike?? BIG BORE is where it’s at!!! 1 Share this post Link to post Share on other sites
_Wilson_™ 6,563 Posted February 24, 2021 yeah, i see the lines plain, and looks like oil residue on the head, plus the mention of burning oil, i believe The forensic investigating team, has figured this one out as for the engine issues. 1 Share this post Link to post Share on other sites
Fishfiles 20,145 Posted February 24, 2021 Take some better pics , put a white rag instead of the zebra print , move your big thumb and get a pic of each side of the piston skirt , the wrist pin doesn't look good , what about a pic of the end of the connecting rod 1 Share this post Link to post Share on other sites
retro 4,048 Posted February 24, 2021 You can pull the lifter cups out now too. Label them Intake/Exhaust as you take them out of the block, then flip them both over so the lifter surfaces that ride on the cam are visible, wipe off the oil on them and take a pic for us. 1 Share this post Link to post Share on other sites
freebo86 291 Posted February 24, 2021 Here is a few more photos. Hope I got most of that you want. Rings are not sharp feeling. don’t see any cross hatching the bore, looks to be shiny. Didn’t check wrist pin. 1 Share this post Link to post Share on other sites
Fishfiles 20,145 Posted February 24, 2021 I would say the valve stems seals have been burnt up for a long time , that's why you would get the puffs of smoke on crank up that you mentioned and all the carbon build up --- I wouldn't even worrying about mic'ing the bore , I see a lot of scratches and a lip , so I would have it bored with a new piston , but if the connecting rod bore for the wrist pin has slack , the rebuild won't last long as the piston will wobble and egg shape the bore and the wrist pin looks rough , which would make me think the rod is in bad shape--- would also pull the cover and screen to see what's in the lower end , if it is full of trash a rebuild won't last long either 4 Share this post Link to post Share on other sites
_Wilson_™ 6,563 Posted February 24, 2021 would you think this bike was sunk at one time, then flushed out ? fish. i see the same as you, scoring, and back a few pages a wet valve stem. plus the scoring on the wrist pin. and not a sign of cross hatch. Share this post Link to post Share on other sites
freebo86 291 Posted February 24, 2021 (edited) 19 minutes ago, Fishfiles said: I would say the valve stems seals have been burnt up for a long time , that's why you would get the puffs of smoke on crank up that you mentioned and all the carbon build up --- I wouldn't even worrying about mic'ing the bore , I see a lot of scratches and a lip , so I would have it bored with a new piston , but if the connecting rod bore for the wrist pin has slack , the rebuild won't last long as the piston will wobble and egg shape the bore and the wrist pin looks rough , which would make me think the rod is in bad shape--- would also pull the cover and screen to see what's in the lower end , if it is full of trash a rebuild won't last long either I measured the rod bore with my calipers and they were within the service limit. Which direction should the rod have slack in? Exhaust to Intake (left-right) or Engine Top-Down? I will have to give @retro suggestion a try and push the wrist pin through and give it a pull/push wobble. What is the cover and screen you are referring to? Edited February 24, 2021 by freebo86 Share this post Link to post Share on other sites
_Wilson_™ 6,563 Posted February 24, 2021 you do have a manual on this bike ? if not you can download one here. https://atvhonda.com/topic/92-service-manual-downloads/ Share this post Link to post Share on other sites
Fishfiles 20,145 Posted February 24, 2021 On the 450 , from looking at this pic , I don't know if you can get the screen #5 out without splitting the case , on the 300s you can , pretty sure I have a 450 with the cover off in the shed , have to take a look for you , well , when you take the cover off today look for that case screen --- Ironic , I am going to be there in this pic today myself , going to change out that #7 oil temp sensors On the wrist pin , you put the wrist pin into the rod horizontally , and try to lift the end vertically , it should be a tight fit with no movement up and down , I would buff the wrist pin clean first as the gall'ed looking ring on your pin could make it feel tighter than it really is 3 Share this post Link to post Share on other sites
Fishfiles 20,145 Posted February 24, 2021 I just looked at my service manual , it shows the screen is inside the crankcase on the 450 , that's a messed up design Share this post Link to post Share on other sites
Goober 1,555 Posted February 24, 2021 (edited) so, next step split the cases? What does he do with the crank? Can it be refurbished? 13000 km isn’t high mileage but there seemed to be a coat of mud or dirt on the outside of the engine. Guess we’ll see if there’s sediment inside. Edited February 24, 2021 by Goober Share this post Link to post Share on other sites
_Wilson_™ 6,563 Posted February 24, 2021 i would have liked to have seen the first oil that came out when he got it, plus a magnet dipped in just to see what it would attract. Share this post Link to post Share on other sites
jdlmodelt 38 Posted February 24, 2021 1 hour ago, Fishfiles said: I just looked at my service manual , it shows the screen is inside the crankcase on the 450 , that's a messed up design It's accessible from the right hand side by removing the right case cover. You don't have to split the case. At least that's how it was set up on the 350. It is recessed into the center cases in a small sump area that as I mentioned is accessible by only removing the right hand clutch cover case. Share this post Link to post Share on other sites
jdlmodelt 38 Posted February 24, 2021 31 minutes ago, Goober said: so, next step split the cases? What does he do with the crank? Can it be refurbished? 13000 km isn’t high mileage but there seemed to be a coat of mud or dirt on the outside of the engine. Guess we’ll see if there’s sediment inside. Is his crank shot? I wouldn't split the case unless it was necessary. Share this post Link to post Share on other sites
Fishfiles 20,145 Posted February 24, 2021 18 minutes ago, jdlmodelt said: It's accessible from the right hand side by removing the right case cover. You don't have to split the case. At least that's how it was set up on the 350. It is recessed into the center cases in a small sump area that as I mentioned is accessible by only removing the right hand clutch cover case. When you mentioned 350 and right hand cover , I realized you must have a 350 A or D , totally different , 350A+D are conventional motorcycle engine configuration , like the 300s , the crankshaft rides side to side and has side covers , on a 450 the crankshaft runs front to rear , has a front and rear cover --- the 350FM and ES are the same as the 450 4 Share this post Link to post Share on other sites
jdlmodelt 38 Posted February 24, 2021 7 minutes ago, Fishfiles said: When you mentioned 350 and right hand cover , I realized you must have a 350 A or D , totally different , 350A+D are conventional motorcycle engine configuration , like the 300s , the crankshaft rides side to side and has side covers , on a 450 the crankshaft runs front to rear , has a front and rear cover --- the 350FM and ES are the same as the 450 Aha! The 450 was the redesign when they started mounting the engines sidways. Yes, mine is an 88 TRX350D. Share this post Link to post Share on other sites
jeepwm69 7,600 Posted February 24, 2021 On 2/22/2021 at 8:08 PM, LedFTed said: that was a while back, now i remember sorta, Moose Racing., or something like that.. it was supposed to be Honda atv parts, but that was missing from the carb gasket set. the only reason i'm dragging this on is, honda atv owners, need to find the best place to get parts for their carburetor or kits. I use Biker Chicks LTD on ebay. Guy's name is Grant. Buy SHINDY. Leave that moose (chy-na) garbage on the shelf. 2 Share this post Link to post Share on other sites
jeepwm69 7,600 Posted February 24, 2021 I guess the big question is, how deep into this rabbit hole do you want to go? Were it mine, I would tear it all the way down at this point. Clean it out, more than likely send the crank to Mr Crankshaft and have him put a rod kit on it (I'm guessing that pin galling means the rod end will allow play, which requires a crank rebuild). Tearing it down and cleaning it out means you KNOW what you have when you put it back together. I slapped a top end on a 500 and it was smoking again within 100 miles because I didn't clean out the bottom end thoroughly, so since then I ALWAYS tear them all the way down.....it's the only way to really know what you have when you're done. Inspect the cam, and if the cam or cam chain guide appears to be worn, get used parts on ebay. If you have a micrometer you can measure to make sure they're good, and if they aren't, you can send them back. (just make sure any parts you buy are not listed as "for parts or not working") I'd plan on a new timing chain, have the top end bored locally to a new Shindy piston. You'll have to spend a little on the bore/piston/gaskets/timing chain, and maybe the crank, but more than likely the rest of the stuff will either be ok, or you can source good used parts on ebay. If you buy all OEM new parts, you're going to spend a ton of cash. I had Rich450ES (think Shadetree, but not as nice) over on the old Foreman board walk me through my first rebuild. No factory service manual, just me posting pics and asking "how" and him (and @toodeep) replying. These things aren't as hard as one would think if you like wrenching on stuff. 4 Share this post Link to post Share on other sites